Sparkol has two great hand-drawn/cartooning tools I find especially useful for creating mental frames for students who sometimes lose context in the active learning environment.

Videoscribe (desktop or MUCH cheaper mobile app). Use their drawings or upload your own for an RSA-animate style creative mindmap you can add voiceover to

Tawe (free version is limited to 2 at a time) where you take a picture of something of yours- drawn or otherwise- then tap around to quickly create zoomed presentation. Works really well with hastily drawn mindmap or other "big picture" stories and timelines.

Explain Everything (iPad) is my go-to app for quick screencasts where I'll mindmap or draw on top of PDFs and Powerpoints. Very easy upload to popular sites like YouTube. Bonus: Lightsaber laser pointer (with sound!)